Process of dyeing.



GUSTAV ADOLF WALDINGER AND CABL FRlEDRIGH-ISERLOTH, OF ELBERFELD, GERMANY,

ASSIGNORS TO FARBENFABRIKEN VORM. MANY, a CORPORATION OF GERMANY.

FRIEDR. BAYER & '00., OF ELBERFELD, GER- rnocnss or DYEING.

Application filed December 29. 1906. Serial No.- 3&94913 Toflall whom "it may concern: Be it known that we, GUSTAV ADOLF WALDINGER and CARL FRIEDRICH ISERLOTH,

citizens of the German Empire, residin at 5 Elberfeld, Kingdom of Prussia, German filmpire, have invented new. and useful Improvementsin Processes of Dyeing, of which the following is a specification.

In French Letters Patent No. 367,921, filed July 9,1906, a recess for dyeing vegetable fibers with en fur coloring matters is described, which rocess' consists in dyeing with these dyestuii usual 'waywith the aid of alkaline sulfids and sulfur coloring matters, butwith' the addition of ammonium salts. By thisprocess' level and uniform shades are obtained which in many cases are even deeper and faster towashing than those obtained without. the employment ofxammonium salts. We have foundthat this favorable action of the ammonium salts seems-to be due to the fact that the ammoniurn' salts neutralize the free alkali present in the alkaline sulfid dye-bath and-that metal salts capable of binding alkali will produce the same result. These metal salts are generally added to the baths in such quantities that a distinctsmell of H,S'is evolved, but care must be taken that no' dyestufl or leuco-compound is precipitated.

.The new process is also suitable for dyeing by machinery.

fully, the following example is given, the

parts being by Weight: A dyebath is preared from 2000 parts of Water, 10- parts of atigen indigo R L extra, 10 parts of crys- Specificatioii of Letters Patent. I

s in baths prepared in the 1 In order to illustrate the new process more Patented Dec. 10, 1907,

galliaed sodium sulfid, and 20 parts of Glauers sodium bicarbonate are added, and 1O0 ,parts of cotton yarn are then dyed in thisbatl tat degrees C. for ihour. The dyed goods are squeezed out, exposed rinsed: j

The process is the same for other dyestufis and for other metal salts capable of binding alkali, such as bisulfate of sodium, bisulfite of sodium, tar, etc. The quantities to be-takenpught' 5"0' to be sufiicient to neutralize the free alkali,

' but care must be'taken' not to add an excess and to avoid the reci itation of the dyestufi'. Having now escri ed our invention and in what manner the same is to be performed,

what we claim, is: 1'. The herein-described process of dyeing vegetable, fibers with sulfur dyestuffs, Which process consists in dyeing vegetable fiber in a dyebath containing sulfur dyes, alkaline sulfids andsalts oiifixed bases, capable of bind-' 'ingalkali, substantially as described.

; 2-. The herein described' process of dyeing vegetable fibers with sulfur dyestuffs, which recess consists in dyeing vegetable fiber ilf'a 1 yebath containing sulfur dyes, alkaline sulfids and sodium bicarbonate, substantially as I described h a r In testimony whereof we have hereunto set our hands in thepresence ofv two subscribing witnesses. v

stem. ADOLF WALDINGER. [a 8.]

\ emu. FRIEDRICH mgr-torn. [u s] Witnesses: OTTO KoNIG,

J. A. RITTE isHAUs.

salt. To this dyebath "5 parts of 40 to the air and alum, acetate of -aluminium, tar-E-.i 

